Geological rock mechanical property testing equipment

Abstract

The invention discloses geological rock mechanical property testing equipment which comprises a machine table, a pressure chamber, a hydraulic system and a loading device, the pressure chamber comprises an upper base and a lower base, one side of the lower base is connected with a pipe connector, and the pipe connector is connected with the hydraulic system through a pressure pipe; clamping assemblies are further connected to the two opposite sides of the lower base, each clamping assembly comprises a base plate, a plurality of through holes arranged in an array mode are formed in each base plate, fixing column matrixes are arranged on the two sides of the lower base respectively, and the through holes correspond to the fixing column matrixes; a sinking groove is formed in the base plate, and a left side clamping piece and a right side clamping piece are arranged in the sinking groove. According to the test method based on the nanoindentation theory, confining pressure is formed through oil pressure pressurization in the pressure chamber for an irregular rock sample, the underground stress state of the rock is simulated, a matched and combined clamping structure is designed for the problem that the irregular rock sample is not easy to clamp and fix, and the problem that confining pressure is not easy to apply by existing indentation test equipment is solved.

Description

Technical Field

[0001] The present invention relates to the technical field related to petroleum geology, and specifically to a testing device for the mechanical properties of geological rocks. Background Art

[0002] Mechanical parameters of rocks such as elastic modulus, Poisson's ratio, and cohesion are important reference sources for obtaining geological data. Generally, the mechanical properties of rocks are obtained through a triaxial testing machine. Conventional triaxial compression tests have always been the main means to understand the mechanical properties of rocks under complex stress states. Conventional triaxial tests generally require a core sample with a diameter of not less than 25 mm. Large-sized rock samples are not easily obtained in actual exploration, especially deep rock cores. It is even more difficult to obtain relatively standard samples. Generally, the rock cuttings obtained from petroleum geological layers are irregular in size and have strong dispersion. It is also very difficult to process them into standard rock samples. Based on the limitations of the above-mentioned conventional triaxial tests, now the nanoindentation technology is used to measure the nano-hardness, elastic modulus, yield strength, and interface bonding force of rock samples under continuous dynamic loads, etc. It has low requirements for the size and shape of the rock core, and the test process is simpler and faster. However, it has an obvious limitation that although it does not require standardized rock samples for triaxial tests, it lacks a confining pressure structure and cannot simulate the stress state of rocks underground. There is also a design of processing the rock sample into a cube and applying confining pressure on its peripheral surface, but this design also requires a lot of time and effort to process the rock sample. Summary of the Invention

[0003] The purpose of the present invention is to provide a testing device for the mechanical properties of geological rocks to solve the problems raised in the above background art.

[0004] To achieve the above purpose, the present invention provides the following technical solution:

[0005] A testing device for the mechanical properties of geological rocks, comprising: a machine table, a pressure chamber, a hydraulic system, and a loading device. The pressure chamber is arranged on the machine table. The pressure chamber includes: an upper base and a lower base. The upper base is detachably connected to the lower base. An activatable pressure rod and a pressure head are arranged inside the upper base. The pressure head is located below the pressure rod and connected thereto. The loading device is located directly above the pressure chamber on the machine table. The loading device includes a fixture and a power device for linearly loading the fixture. The interior of the lower base is a cavity for placing a rock sample. One side of the lower base is connected with a pipe interface, and the pipe interface is connected to the hydraulic system through a pressure pipe;

[0006] On opposite sides of the lower base, there are also connected clamping components. Each clamping component includes a substrate. Multiple through-holes arranged in an array are provided on the substrate. On both sides of the lower base, there are respectively arranged fixed column matrices. Each fixed column matrix is composed of multiple optical rods arranged in a rectangular array. The optical rods are slidably connected to the lower base. The inner end of the optical rod is conical, and the through-holes correspond to the fixed column matrices. Inside the substrate, there is a sunken groove. Inside the sunken groove, there is a left clamping member and a right clamping member. The left clamping member and the right clamping member include several groups of clamping rods. An arc groove corresponding to the through-hole is provided on the clamping rod. The clamping rods of the left clamping member and the right clamping member are symmetrically located on the left and right sides of the through-hole column array respectively.

[0007] As a further scheme of the present invention: The left clamping member and the right clamping member are slidably installed in the sunken groove, and gears are provided in the sunken groove. The gears are respectively meshed with the rack structures on the left clamping member and the right clamping member.

[0008] As a further scheme of the present invention: The end of the left clamping member is connected to a top rod. The end of the top rod extends outwardly beyond the substrate and is arranged relative to the slider.

[0009] As a further scheme of the present invention: Sliders are provided on both sides of the substrate. Clasps are provided on the inner sides of the sliders. On the edge of the lower base, there are card slots corresponding to and cooperating with the clasps.

[0010] As a further scheme of the present invention: A rubber ring is provided at the inner end position of the through-hole.

[0011] As a further scheme of the present invention: A sealing ring is provided between the bottom end surface of the upper base and the top of the lower base.

[0012] As a further scheme of the present invention: The upper base and the lower base are fixedly connected through a connecting seat.

[0013] As a further scheme of the present invention: A mica electric heating plate is further provided inside the lower base.

[0014] As a further scheme of the present invention: The indenter is a diamond indenter.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: Based on the test method of nanoindentation theory, for irregular rock samples, confining pressure is formed by pressurizing the oil pressure in the pressure chamber to simulate the stress state of rocks underground. And a clamping structure combined with a supporting structure is designed for the problem that irregular rock samples are not easy to clamp and fix, solving the main limitations that the existing indentation test equipment is not easy to apply confining pressure and still has relatively high requirements for the standard of rock samples. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the present invention.

[0017] Figure 2 This is a schematic structural diagram of the pressure chamber in the present invention.

[0018] Figure 3 This is an internal sectional view structural diagram of the pressure chamber in the present invention.

[0019] Figure 4 This is a longitudinal sectional view structural diagram of the substrate in the present invention.

[0020] Figure 5 This is a cross-sectional view structural diagram of the substrate in the present invention.

[0021] In the figure, 1 is a machine platform; 2 is a pressure chamber; 21 is an upper base; 22 is a lower base; 221 is a card slot; 222 is a matrix of fixing columns; 223 is a pipe interface; 224 is a mica electric heating plate; 23 is a pressure rod; 24 is a pressure head; 25 is a connecting seat; 3 is a hydraulic system; 4 is a loading device; 41 is a fixture; 5 is a substrate; 51 is a slider; 511 is a buckle; 52 is a through hole; 521 is a rubber ring; 53 is a left clamping member; 54 is a right clamping member; 55 is a gear; 56 is a ejector rod; 6 is a rock sample. Specific embodiments

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0023] Please refer to Figures 1 to 3 , in the embodiment of the present invention, a geological rock mechanics property testing device includes: a machine platform 1, a pressure chamber 2, a hydraulic system 3 and a loading device 4. The pressure chamber 2 is arranged on the machine platform 1. The pressure chamber 2 includes: an upper base 21 and a lower base 22. The upper base 21 is detachably connected to the lower base 22. Specifically, the upper base 21 and the lower base 22 are fixedly connected through a connecting seat 25.

[0024] The upper base 21 is internally provided with a movable pressure rod 23 and a pressure head 24. The pressure head 24 is located below the pressure rod 23 and is connected thereto. The pressure head 24 can be a diamond pressure head. The loading device 4 is located directly above the pressure chamber 2 on the machine platform 1. The loading device 4 includes a fixture 41 and a power device for linearly loading the fixture 41, such as a hydraulic cylinder connected to the hydraulic system 3. The interior of the lower base 22 is a cavity and can place a rock sample 6. One side of the lower base 22 is connected with a pipe interface 223. The pipe interface 223 is connected to the hydraulic system 3 through a pressure pipe; a mica electric heating plate 224 is also arranged in the lower base 22;

[0025] Such asFigure 4 , clamping components are also connected to opposite sides of the lower base 22. The clamping components include a substrate 5, and a plurality of through holes 52 arranged in an array are provided on the substrate 5. Fixed column matrices 222 are respectively arranged on both sides of the lower base 22. The fixed column matrices 222 are composed of a plurality of optical rods arranged in a rectangular array. The optical rods are slidably connected to the lower base 22, and the inner ends of the optical rods are conical. The through holes 52 correspond to the fixed column matrices 222. Sliders 51 are arranged on both sides of the substrate 5, and buckles 511 are arranged on the inner sides of the sliders 51. A clamping groove 221 corresponding to the buckle 511 is arranged on the edge of the lower base 22, so that the substrate 5 can be attached to the side surface of the lower base 22. After the slider 51 is slid and buckled, the slider 51 is fixed tightly by a bolt fastener, so that the substrate 5 is tightly fixed on the side surface of the lower base 22; a sunk groove is arranged inside the substrate 5, and a left clamping member 53 and a right clamping member 54 are arranged in the sunk groove. The left clamping member 53 and the right clamping member 54 include a plurality of groups of clamping rods, and arc grooves corresponding to the through holes 52 are arranged on the clamping rods. The clamping rods of the left clamping member 53 and the right clamping member 54 are symmetrically located on the left and right sides of the column array of the through holes 52 respectively. The left clamping member 53 and the right clamping member 54 are slidably installed in the sunk groove, and a gear 55 is arranged in the sunk groove. The gear 55 meshes with the rack structures on the left clamping member 53 and the right clamping member 54 respectively. The end of the left clamping member 53 is connected to a push rod 56, and the end of the push rod 56 extends outwards beyond the substrate 5 and is arranged relative to the slider 51.

[0026] When performing an indentation test on the rock sample 6 in the present invention, first, a loading surface is processed on the rock sample 6 by means of cutting, grinding, argon ion polishing, etc. After a heat-resistant film is coated on the surface of the rock sample 6 except for the loading surface, it is placed into the lower base 22. The loading surface is kept horizontal by horizontal measurement. If it is difficult to place it stably, a plane parallel to the loading surface can also be processed at the lower end of the rock sample 6. Subsequently, the upper base 21 is connected and fixed; the clamp 41 is moved down to the position of the pressure rod 23 to clamp and fix the pressure rod 23; then the substrate 5 is connected to the lower base 22. During the process, the through holes 52 correspond to the fixed column matrices 222, and a rubber ring 521 is arranged at the inner end position of the through holes 52, as Figure 5, the inner diameter of the rubber ring 521 is slightly smaller than the diameter of the polished rod. When assembling the substrate 5, the polished rod first contacts the rubber ring 521. The rubber ring 521 generates frictional force on the polished rod to push the polished rod to move inward. After the substrate 5 is closed, the inner end of the polished rod abuts against the surface of the rock sample 6 and adapts to the surface shape of the rock sample 6. At this time, the polished rod cannot loosen due to the action of the rubber ring 521. Subsequently, the slider 51 is clamped in and tightened by fasteners. During the tightening process, when the slider 51 contacts the ejector rod 56, it pushes the left clamping member 53 to move, synchronously causing the right clamping member 54 to move relatively driven by the gear 55, so as to clamp all the polished rods in the through hole 52 therein. In this way, the substrate 5, the lower base 22 and the fixed column matrix 222 are assembled and fixed. The rock sample 6 is fixed by the fixed column matrix 222 abutting against its surface. At this time, the clamping of the pressure chamber 2 is completed, and the rubber ring 521 plays a sealing role. Subsequently, pressure oil is pumped into the pressure chamber 2 through the hydraulic system 3. After the required oil pressure is reached, pressure holding is carried out. The oil pressure simulates the confining pressure on the surface of the rock sample 6. Subsequently, the loading device 4 drives the indenter 24 to perform multiple dot matrix presses, and the load-displacement curve is collected, so that the strength characteristic parameters of the rock sample can be calculated.

[0027] Based on the rock mechanics characteristic testing equipment of the present invention, samples taken from different fracture zones are respectively subjected to regular and irregular treatments, the same confining pressure is applied, and mechanical tests are carried out. The error between the two is 4.4-6.93%. The measurement results of the present invention are closer to the actual situation, achieving the initial goal of the present invention.

[0028]

[0029] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description.

[0030] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A geological rock mechanical properties testing device, comprising: A machine (1), a pressure chamber (2), a hydraulic system (3) and a loading device (4), wherein the pressure chamber (2) is arranged on the machine (1), and is characterized in that: the pressure chamber (2) comprises: an upper base (21) and a lower base (22), wherein the upper base (21) is detachably connected to the lower base (22), wherein a movable pressure rod (23) and a pressure head (24) are arranged in the upper base (21), wherein the pressure head (24) is located below the pressure rod (23) and connected thereto, wherein the loading device (4) is located directly above the pressure chamber (2) on the machine (1), wherein the loading device (4) comprises a fixture (41) and a power device for linearly loading the fixture (41), wherein the interior of the lower base (22) is a cavity, wherein one side of the lower base (22) is connected to a pipe interface (223), wherein the pipe interface (223) is connected to the hydraulic system (3) via a pressure pipe; The lower base (22) is also connected to clamping assemblies on two opposite sides. The clamping assembly comprises a base plate (5). A plurality of through holes (52) arranged in an array are arranged on the base plate (5). Fixed column matrices (222) are respectively arranged on both sides of the lower base (22). The fixed column matrices (222) are composed of a plurality of light rods arranged in a rectangular array. The light rods are slidably connected to the lower base (22). The inner ends of the light rods are conical. The through holes (52) correspond to the fixed column matrices (222). A sink groove is arranged inside the base plate (5). A left clamping piece (53) and a right clamping piece (54) are arranged in the sink groove. The left clamping piece (53) and the right clamping piece (54) comprise a plurality of groups of clamping rods. The clamping rods are provided with arc grooves corresponding to the through holes (52). The clamping rods of the left clamping piece (53) and the right clamping piece (54) are symmetrically located on the left and right sides of the through hole (52) array.

2. A geological rock mechanical properties testing device according to claim 1, characterized in that: The left clamping member (53) and the right clamping member (54) are slidably installed in the sink, and a gear (55) is arranged in the sink. The gear (55) is respectively meshed with the rack structures on the left clamping member (53) and the right clamping member (54).

3. A geological rock mechanical properties testing device according to claim 2, characterized in that: The end of the left clamping member (53) is connected to a push rod (56), and the end of the push rod (56) extends outwardly to the outside of the base plate (5) and is arranged relative to the slider (51).

4. A geological rock mechanical properties testing device according to claim 1, characterized in that: Slide blocks (51) are arranged on both sides of the base plate (5), buckles (511) are arranged inside the slide blocks (51), and a clamping groove (221) corresponding to the buckle (511) is arranged on the edge of the lower base (22).

5. The geological rock mechanical properties testing equipment according to claim 1, characterized in that: A rubber ring (521) is provided at the inner end of the through hole (52).

6. A geological rock mechanical properties testing device according to claim 1, characterized in that: A sealing ring is provided between the bottom end surface of the upper base (21) and the top of the lower base (22).

7. The geological rock mechanical properties testing equipment according to claim 1, characterized in that: The upper base (21) and the lower base (22) are fixedly connected via a connecting base (25).

8. The geological rock mechanical properties testing equipment according to claim 1, characterized in that: A mica electric heating plate (224) is arranged in the lower base (22).

9. The geological rock mechanical properties testing equipment according to claim 1, characterized in that: The indenter (24) is a diamond indenter.

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